package com.atguigu.gulimail.product.service.impl;

import com.atguigu.gulimail.product.service.CategoryBrandRelationService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimail.product.dao.CategoryDao;
import com.atguigu.gulimail.product.entity.CategoryEntity;
import com.atguigu.gulimail.product.service.CategoryService;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    CategoryBrandRelationService categoryBrandRelationService;

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //2.组装成父子的数据结构
        List<CategoryEntity> levelMenu = entities.stream().filter(e -> (
            e.getParentCid() == 0)
        ).map((menu) -> {
            menu.setChildren(getChildren(menu,entities));
            return menu;
        }).sorted(
                (menu1,menu2) ->{
                    //菜单的排序
                    return (menu1.getSort() == null?0:menu1.getSort()) - (menu2.getSort() == null?0:menu2.getSort());
                }
        ).collect(Collectors.toList());

        return levelMenu;
    }

    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 检查当前菜单是否被别的地方引用

        baseMapper.deleteBatchIds(asList);
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId,paths);
        Collections.reverse(parentPath);
        return parentPath.toArray(new Long[parentPath.size()]);
    }

    /**
     * 级联更新所有关联的数据
     * @param category
     */
    @Override
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategory(category.getCatId(),category.getName());
    }

    private List<Long> findParentPath(Long catelogId, List<Long> paths) {
        //收集当前节点id
        paths.add(catelogId);

        CategoryEntity byId = this.getById(catelogId);
        if (byId.getParentCid() != 0) {
            findParentPath(byId.getParentCid(),paths);
        }
        return paths;
    }

    /**
     * 递归查找所有菜单子菜单
     * @param root
     * @param all
     * @return
     */
    private List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all) {
        List<CategoryEntity> children = all.stream().filter(e -> {
            return e.getParentCid().equals(root.getCatId());
        }).map(e ->{
            //找到子菜单
            e.setChildren(getChildren(e,all));
            return e;
        }).sorted((menu1,menu2) ->{
            //菜单的排序
            return (menu1.getSort() == null?0:menu1.getSort()) - (menu2.getSort() == null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return children;
    }

}